Similar resemblance in the hyphae of living fungus Rhyzoctonia solani (left) and ancient fungus Reduviasporonites (right). (Rhizoctonia image courtesy of Lane Tredway, The American Phytopathological Society)

At the end-Permian extinction event 250 million years ago, 70% of land organisms and 95% of marine organisms went extinct. Forests of conifer relatives were also wiped out … and their demise may have been helped by pathogenic soil fungi suggest UCMP's Cindy Looy and colleagues Henk Visscher, Utrecht University, Netherlands, and Mark Sephton, Imperial College, London.

Most researchers accept that extensive volcanism at the end of the period, resulting in major changes in global climate, was the root cause of the Permian mass extinction. Under stress from these climate changes, the conifer forests may have become more susceptible to attack from the soil-borne pathogenic fungi, speeding widespread tree mortality. If so, could our own changing climate trigger attacks by living pathogenic fungi on today's stressed forests?

Learn more about Looy et al.'s studies of fossil and living pathogenic fungi: